Hi tweets,

Many years ago I shared a house with a UW zoology grad student, Wayne Potts;
he had been studying dunlin flight maneuvers, and Kathy's post prompted me
to look him up on the web. This pasted text is from
http://www.stuartwilde.com/Learn/SW_learn_Society_Spirit_Ritual_Part2.htm

WAYNE POTTS AND THE MANEUVER WAVES OF BIRDS

"As another familiar example of the super-organism concept, consider schools
of fish: when predators swim into a school, the fish dart quickly to the
side in a coordinated way in order to clear a path through the middle. They
move very fast in response to quite unexpected stimuli, yet they do not bump
into each other. The same is true of flocks of birds. A whole flock can bank
as one without the birds bumping into each other.

Recently, studies investigating the banking of large flocks of dunlins by
American researcher Wayne Potts have been conducted. He filmed their
maneuvers at a very rapid rate of exposure, so that he could later slow the
process down and examine it frame by frame. When he did so, he found that
the rate of propagation of what he calls the "maneuver wave" is extremely
fast: about 20 milliseconds from bird to bird. This is much faster than the
birds' minimum reaction time to stimuli. He measured their startle reaction
time using dunlins in the laboratory in dark or dim light. He set off
photographic flashbulbs and measured how long it took the birds to react. He
found that it took the individual birds about 80-100 milliseconds; that is,
they reacted as individuals four to five times more slowly than the rate at
which the maneuver wave moved from bird to bird. The banking maneuver could
begin anywhere within the flock, at the front or back or at the side. It was
usually initiated by a single bird or a small group of birds, and then
propagated outwards much faster than could be explained by any simple system
of visual cuing and response to stimuli."

Wayne is now a professor in the Utah Biology Dept.

more regarding bird maeuvering and Wayne Potts:
http://www.straightdope.com/mailbag/mflockswoop.html

Kevin Li
Ballard, USA